\begin{tabular}{l*{11}{c}}
\hline
                 &\multicolumn{1}{c}{Yr}&\multicolumn{1}{c}{Yr}&\multicolumn{1}{c}{Yr}&\multicolumn{1}{c}{Yr}&\multicolumn{1}{c}{Yr}&\multicolumn{1}{c}{Yr}&\multicolumn{1}{c}{Yr}&\multicolumn{1}{c}{Yr}&\multicolumn{1}{c}{Yr}&\multicolumn{1}{c}{Yr}&\multicolumn{1}{c}{Yr}&\multicolumn{1}{c}{Yr}\\         &\multicolumn{1}{c}{4}&\multicolumn{1}{c}{5}&\multicolumn{1}{c}{6}&\multicolumn{1}{c}{7}&\multicolumn{1}{c}{8}&\multicolumn{1}{c}{9}&\multicolumn{1}{c}{10}&\multicolumn{1}{c}{11}&\multicolumn{1}{c}{12}&\multicolumn{1}{c}{13}&\multicolumn{1}{c}{14}\\ \hline  \emph{Second stage}\\
Enrollment  &       4.951***&       8.125***&       9.718***&      11.809** &      14.718** &      18.813** &      23.917** &      27.476** &      32.322** &      42.018** &      44.811** \\
            &     (1.203)   &     (2.437)   &     (3.653)   &     (5.215)   &     (6.758)   &     (8.561)   &    (10.437)   &    (12.307)   &    (14.263)   &    (16.271)   &    (18.210)   \\
\hline
Controls    &         Yes   &         Yes   &         Yes   &         Yes   &         Yes   &         Yes   &         Yes   &         Yes   &         Yes   &         Yes   &         Yes   \\
F-stat      &         227   &         230   &         234   &         234   &         232   &         236   &         227   &         225   &         225   &         229   &         227   \\
N           &        3667   &        3654   &        3635   &        3609   &        3577   &        3549   &        3509   &        3478   &        3430   &        3373   &        3335   \\
Mean of Y   &       11.81   &       26.66   &       42.50   &       59.01   &       76.31   &       94.89   &      114.47   &      134.93   &      156.88   &      180.61   &      205.39   \\
\hline
\end{tabular}
